The present invention relates to a method of contact-connecting safety-monitored synthetic fiber ropes: it relates to suitable devices for contact-connecting as well as the safety-monitored synthetic fiber ropes themselves.
Synthetic fiber ropes are used as stationary and as running ropes for many different purposes. Used either way, they take heavy loads. In the case of running ropes, this tensile loading is complemented by flexural loading that reduces their service lifetime due to the number of load ranges in which they operate. To detect an operationally critical state of wear of the synthetic fiber ropes, their so-called replacement-readiness, in advance of failure of the synthetic fiber ropes, the safety of their condition is monitored.
Such monitoring of the safety of synthetic fiber ropes is know from the European patent specification EP 0 731 209 B1 of the applicant. Therein suspension ropes are used which consist of electrically insulating synthetic fibers, and electrically conducting indicator fibers that are relatively less strong than the insulating fibers. The indicator fibers are bundled together with the synthetic fibers to form strands. An electric voltage is applied to the indicator fibers so as to measure electrically the snapping or breaking of the indicator fibers. A disadvantage of this method of monitoring the safety of suspension ropes is its labor-intensive construction. The ends of the suspension ropes are stripped of their rope sheath, and the indicator fibers laid bare. Indicator fibers are connected in series by means of free indicator fibers of one end of a synthetic fiber rope being joined together into pairs by use of individual connecting elements. The large number of indicator fibers built into each synthetic fiber rope makes this method of construction expensive.
It is the purpose of the present invention to provide a low-cost and reliable method of contact-connecting safety-monitored synthetic fiber ropes. The method, and the workpieces used to execute the method, shall be compatible with existing standards for elevator construction.
The present invention simplifies the method described in the above-identified patent specification EP 0 731 209 for the construction of safety-monitored synthetic fiber ropes. Instead of laying bare individual electrically conducting indicator fibers of the strands of the rope ends, then electrically connecting pairs of bare indicator fibers of a rope end by means of a large number of connector sockets, and finally binding them individually with insulating material, rope ends are provided with a contact-connecting device which connects more than two indicator fibers together in an electrically conducting manner.